Methods of cutting laminated strip material

ABSTRACT

A method of cutting a laminated strip of material having soft and hard layers in which a groove is cut in the soft layer up to the hard layer and the hard layer is cut through in a plane between the sidewalls of the groove. The width of the groove is sufficient to avoid distortion of the hard layer caused by cutting of the hard layer from reaching the interfaces between the soft and hard layers on either side of the groove.

United States Patent Clark [451 Apr. 18, 1972 [5 4] METHODS OF CUTTINGLAMINATED [56] References Cited STRIP MATERIAL 72 I M R am N C] k I k hUNITED STATES PATENTS nventor: artin on ewton ar a 1 England C en m3,517,576 6/1970 Hilty et al. ..s3/5 3,604,295 9/1971 Clark et al...83/9 [73] Asslgneez Vandervell Products Limited, London, En-

gland Primary Examiner-Frank T. Yost [22] Filed: July 20, 1970AttorneyMawhinney & Mawhinney A method of cutting a laminated strip ofmaterial having soft [30] Foreign Appncafion Priority Dam and hardlayers in which a groove is cut in the soft layer up to Oct. 22, 1969Great Britain ..5l,835/69 the hard layer and the hard layer is cutthrough in a plane between the sidewalls of the groove. The width of thegroove Cl 9. is sufficient to avoid distortion of the hard layer causedby 83/519, 83/675, 83/686 cutting of the hard layer from reaching theinterfaces between [51] Int. Cl- ..B26d 3/06, 326d 9/00 the soft andhard layers on either side of the groove. [58] Field ofSearch ..83/5,6,9, 39,519,686

5 Claims, 7 Drawing Figures METHODS OF CUTTING LAMINATED STRIP MATERIALThis invention relates to methods of cutting through laminated strips ofmaterial of the type comprising two adjacent layers which are bonded toone. another and in which one of the adjacent layers is relatively softand the other of the adjacent layers is relatively hard. For example thelaminated strip may comprise a steel or other metallic backing having alayer of polymeric material on one side thereof, although the inventionis not restricted to strips having two layers and could be used forstrips having three or more layers.

The invention provides a method of cutting a laminated strip material ofthe type defined comprising a first cutting operation which forms agroove in the soft layer of material which groove extends up to theinterface with the harder layer and a second cutting operation in theharder layer in a plane located between the sides of the groove in thesoft'layer, the width of which groove is such that distortion of theharder layer due to the second cutting operation does not reach theinterfaces between the soft layer and the harder layer on either side ofthe groove.

The second cutting operation may be carried out by cooperating shearingmembers which engagethe harder layer on either side thereof withoutengagingthe softer layer.

The groove formed in the softer layer may taper towards the bottom layerat the interface with the harder layer.

The walls of the groove may be formed so that they are inclined atsubstantially 45 to the interface with the harder layer.

Grooves may be cut in the softer layer successively at a number ofspaced locations and the cuts may be completed by cutting the harderlayer at said locations simultaneously.

The invention also provides an apparatus for carrying out any of themethods referred to above in which a groove is formed in the soft layerof the material comprising a tool having a cutting edge for forming agroove, means for moving the tool relatively to the strip to form agroove at the required 10- cation and co-operating shearing members forengaging the face of the harder layer within the groove and the oppositeside of the harder layer to shear through the layer in a plane locatedcentrally between the sides of the groove.

In the case where the harder layer is required to be cut simultaneouslyat at least two locations, one shearing member may be provided havingtwo projections which enter the grooves formed in the soft layer on thestrip each of which projections may have a shearing edge, the memberhaving a recess between the projections for accommodating the part ofthe soft layer of material between the locations of the two cuts and twospaced shearing members for engaging the other side of the strip.

The shearing members may comprise rollers formed with said projectionsand shearing edges between which the strip is fed.

The following is a description of one embodiment of the inventionreference being made to the accompanying diagrammatic drawings in which:

FIG. 1 is a diagrammatic view of an apparatus for cutting an upper layerof a laminated strip;

FIG. 2 is a side elevation view of a tool used in the apparatus of FIG.1;

FIG. 3 is an end elevation view of the too] shown in FIG. 2;

FIG. 4 is a sectional view of an apparatus for completing the cutting ofthe strip;

FIG. 5 is a transverse sectional view of a laminated strip which ispartially severed in directions along its length;

FIG. 6 is a view of an apparatus for completing the longitudinalsevering of the strip shown in FIG. 5; and

FIG. 7 is a detailed view of part of the apparatus shown in FIG. 6.

Referring firstly to FIG. 1 of the drawings there is shown a strip oflaminated material indicated generally by the reference numeral 10 whichcomprises a hard metallic backing 11 having a thickness of 0.051 inchesand a layer 12 of a soft polymeric material having a thickness of 0.009inches bonded to the upper face of the backing element. The strip 10 isfed step by step to an apparatus which comprises a head 30 which isslidably mounted on horizontal rods 31. Mounted in the head 30 is a tool32 the lower end of which projects below the head 30. The tool 32 whichis shown in greater detail in FIGS. 2 and 3 of the drawings has cuttingedges indicated at 33 at its lower end with a recess 32a between them.As shown in FIG. 2 each cutting edge consists of a central horizontaledge part 34 which is flanked by two edge parts 35 inclined upwardly at45to the horizontal portion.

The strip 10 which is fed by means not shown into the plane of the paperas viewed in FIG. 1 of the drawings rests on a supporting member 36which is mounted on a mechanism indicated at 37 which raises and lowersthe member 36. Edge portions of the upper face of the strip on eitherside of the location where the tool 30 is to operate engage 'under fixedplates 38 to which the strip 10 is clamped by raising of the member 36after the strip has been advanced by the required amount. The head 30 isthen traversed from right to left and the tool 30 cuts through the softlayer 12 of the strip. In so doing the edge part 34 of the leadingcutting edge cuts the bond between the soft layer 12 and backing 11 andthe inclined edge parts 35 cut inclined walls in the soft layer 12 toform a groove in the soft layer 12. The mechanism 37 is then operated torelease the strip for a further advance after which the head 30 crossesthe strip in the opposite direction.

The grooved strip is then passed to a shearing apparatus illustrated inFIG. 4. The shearing apparatus upper and lower shearing members 50 and61 respectively. The upper shearing member 60 extends across the widthof the strip 10 and is reciprocated in a vertical direction by means(not shown). The shearing member 60 has a cutting edge 62 at the lowerend thereof and a recess 63 is formed in the lower end of the memberadjacent the edge 62 to provide clearance over the soft layer of thestrip. The lower shearing member 61 has a shearing edge 64 and isarranged so that as the member 60 is moved downwardly the two edges 62,64 co-operate to shear through the backing 11.

The strip is positioned so that the backing is sheared along the centerline of the groove formed in the soft layer 12 and the width of thegroove is such that distortion of upper part of the backing does notextend to the bond between the layers 11 and 12 of the strip on eitherside of the groove.

Referring now to FIG. 5 of the drawings there is shown a transversecross-section of a laminated strip 10 in the upper layer 12 of whichlongitudinal grooves 40 have been formed. The grooves 40 are formed bysimilar tools to the tool 32 of the apparatus shown in FIG. 3. The widthof the base of the groove is such that the harder material can besheared along planes indicated at 41 located centrally with respect tothe groove without the deformation caused by the shearing operationsspreading to parts of the harder layer which are bonded to the layer 12on either side of the groove. In this case the width of the base of thegroove is 0.040 inches. The sidewalls of the grooves 40 are inclined at45 to the base of the groove.

FIG. 6 shows an apparatus into which the strip of FIG. 4 is fed to shearthe backing layer of the strip. The apparatus comprises a number ofoverlapping upper and lower rollers between which the strip is fed. Theupper rollers are spaced apart on a common motor-driven drive shaft (notshown) and the lower rollers are spaced apart on a further commonmotordriven drive shaft (not shown). The upper rollers comprise tworollers 42, 42a each of which has peripheral cutting edges 43. As bestseen in FIG. 9 of the drawings a flat 44 is formed around the outersurface of the roller adjacent each cutting edge 43 and between the twoflats 44 the roller has a recess 45. The sidewalls 46 of the recess areinclined at approximately 45 to the bottom wall of the recess. The axialspacing of the two cutting edges 43 on the roller is identical to thespacing between planes 41 on the strip 10 where two adjacent cuts arerequired to be made. The width of the flats 44 in this case is 0.010inches so that each flat engages only a part of the upper surface of thelayer 11 within the groove and the inclined faces 46 are spaced from theadjacent inclined face of the groove. Likewise the depth of the recess45 is such that the base of the recess is spaced from the upper surfaceof the layer 12. The right hand cutting edge 43 on the roller 42co-operates with a cutting edge 47 formed around the left hand peripheryof a lower roller 48. The cutting edges trim away an excess edge portion49 of the strip. The left hand cutting edge 43 of the roller 42co-operates with a cutting edge 50 formed around the right handperiphery of a lower plain roller 51 which has another cutting edge 52around its left hand periphery which co-operates with the right handcutting edge 43 on the left hand roller 42. The left hand cutting edge43 on the roller 42a co-operates in turn with a cutting edge 33 formedat the left hand end of another lower plain roller 54 which has acutting edge 55 at its left hand periphery which co-operates with thecutting edge 56 of an upper roller 57 which is similar to the roller 48and trims away excess strip 58 at the left hand end of the strip. Thestrip is thus divided into four longitudinally extending strips 59 withtwo waste pieces 49 and 58. Each of the lengths 59 of strip is thendivided transversely into portions from which half bearing liners areformed by the apparatus shown in FIGS. 1 to 3 described above.

lclaim:

l. A method of cutting a laminated strip material of the type definedhereinbefore comprising a first cutting operation which forms a groovein the soft layer of material which groove extends up to the interfacewith the harder layer and a second cutting operation in the harder layerin a plane located between the sides of the groove in the soft layer,the width of which groove is such that distortion of the harder layerdue to the second cutting operation does not reach the interfacesbetween the soft layer and the harder layer on either side of thegroove.

2. A method as claimed in claim 1 wherein the second cutting operationis carried out by co-operating shearing members, which engage the harderlayer on either side thereof without engaging the softer layer.

3. A method as claimed in claim 1 wherein the groove formed in thesofter layer tapers towards the bottom layer at the interface with theharder layer.

4. A method as claimed in claim 3 wherein the walls of the groove areformed so that they are inclined at substantially 45 to the interfacewith the harder layer.

5. A method as claimed in claim 1 wherein grooves are cut in the softerlayer successively at a number of spaced locations and the cuts arecompleted by cutting the harder layer at said locations simultaneously.

1. A method of cutting a laminated strip material of the type defined hereinbefore comprising a first cutting operation which forms a groove in the soft layer of material which groove extends up to the interface with the harder layer and a second cutting operation in the harder layer in a plane located between the sides of the groove in the soft layer, the width of which groove is such that distortion of the harder layer due to the second cutting operation does not reach the interfaces between the soft layer and the harder layer on either side of the groove.
 2. A method as claimed in claim 1 wherein the second cutting operation is carried out by co-operating shearing members, which engage the harder layer on either side thereof without engaging the softer layer.
 3. A method as claimed in claim 1 wherein the groove formed in the softer layer tapers towards the bottom layer at the interface with the harder layer.
 4. A method as claimed in claim 3 wherein the walls of the groove are formed so that they are inclined at substantially 45* to the interface with the harder layer.
 5. A method as claimed in claim 1 wherein grooves are cut in the softer layer successively at a number of spaced locations and the cuts are completed by cutting the harder layer at said locations simultaneously. 